An age- and cause decomposition of differences in life expectancy between residents of Inuit Nunangat and residents of the rest of Canada, 1989 to 2008.
This study quantifies differences in life expectancy between residents of Inuit Nunangat and people in the rest of Canada; estimates the contribution of specific causes of death to the differences; and examines these differences over time, by sex and by age group.
A geographic approach was used to decompose differences in life expectancy for residents of Inuit Nunangat, compared with people living outside this geographic area. Differences in life expectancy by cause, sex, and age group were calculated using the discrete method of decomposition and were applied to abridged life tables. Causes of death were classified according to Global Burden of Disease categories. Attributable causes of death were calculated for causes amenable to medical intervention and for smoking-related diseases.
The largest contributor to life expectancy differences between males in Inuit Nunangat and the rest of Canada was injury, particularly self-inflicted injury at ages 15 to 24. For females, the largest contributors were malignant neoplasm and respiratory disease at ages 65 to 79.
The gap in life expectancy between residents of Inuit Nunangat and the rest of Canada can be attributed to specific groups of causes occurring within specific age ranges.
Hospital records lack information about country of birth. This study describes a method for calculating hospitalization rates by the percentage of foreign-born in Census Dissemination Areas (DAs).
Data from the 2006 Census were used to classify DAs by the percentage of the foreign-born population who lived in them. Quintile and tercile thresholds were created to classify DAs as having low to high percentages of foreign-born residents. This information was appended to the 2005/2006 Hospital Morbidity Database via postal codes. Age-sex standardized hospitalization rates were calculated for low to high foreign-born concentration DAs, nationally and subnationally.
Nationally, quintile thresholds had better discriminatory power to detect variations in hospitalization rates by foreign-born concentration, but tercile thresholds produced reliable results at subnational levels. All-cause hospitalization rates were lowest among residents of the high foreign-born concentration terciles. Similar gradients emerged in hospitalization rates for heart disease, diseases of the circulatory system, and mental health conditions. The pattern varied more at the subnational level.
With this approach, administrative data can be used to calculate hospitalization rates by foreign-born concentration.
The aim of this study was to examine spatial clustering of obesity and/or moderate physical activity and their relationship to a neighborhood's built environment. Data on levels of obesity and moderate physical activity were derived from the results of a telephone survey conducted in 2006, with 1,863 survey respondents in the study sample. This sample was spread across eight suburban neighborhoods in Metro Vancouver. These areas were selected to contrast residential density and income and do not constitute a random sample, but within each area, respondents were selected randomly. Obesity and moderate physical activity were mapped to determine levels of global and local spatial autocorrelation within the neighborhoods. Clustering was measured using Moran's I at the global level, Anselin's Local Moran's I at the local level, and geographically weighted regression (GWR). The global-level spatial analysis reveals no significant clustering for the attributes of obesity or moderate physical activity. Within individual neighborhoods, there is moderate clustering of obesity and/or physical activity but these clusters do not achieve statistical significance. In some neighborhoods, local clustering is restricted to a single pair of respondents with moderate physical activity. In other neighborhoods, any moderate local clustering is offset by negative local spatial autocorrelation. Importantly, there is no evidence of significant clustering for the attribute of obesity at either the global or local level of analysis. The GWR analysis fails to improve significantly upon the global model-thus reinforcing the negative results. Overall, the study indicates that the relationship between the urban environment and obesity is not direct.
There are several plausible mechanisms whereby either short or long term exposure to pollution can increase the risk of stroke. Over the last decade, several studies have reported associations between short-term (day-to-day) increases in ambient air pollution and stroke. The findings from a smaller number of studies that have looked at long-term exposure to air pollution and stroke have been mixed. Most of these epidemiological studies have assigned exposure to air pollution based on place of residence, but these assignments are typically based on relatively coarse spatial resolutions. To date, few studies have evaluated medium-term exposures (i.e, exposures over the past season or year). To address this research gap, we evaluated associations between highly spatially resolved estimates of ambient nitrogen dioxide (NO2), a marker of traffic pollution, and emergency department visits for stroke in Edmonton, Canada.
This was a case-control study with cases defined as those who presented to an Edmonton area hospital emergency department between 2007 and 2009 with an acute ischemic stroke, hemorrhagic stroke, or transient ischemic attack. Controls were patients who presented to the same emergency departments for lacerations, sprains, or strains. A land-use regression model provided estimates of NO2 that were assigned to the place of residence. Logistic regression methods were used to estimate odds ratios for stroke in relation to an increase in the interquartile range of NO2 (5 ppb), adjusted for age, sex, meteorological variables, and neighborhood effects.
The study included 4,696 stroke (cases) and 37,723 injury patients (controls). For all strokes combined, there was no association with NO2. Namely, the odds ratio associated with an interquartile increase in NO2 was 1.01 (95% confidence interval {CI}: 0.94-1.08). No associations were evident for any of the stroke subtypes examined.
When combined with our earlier work in Edmonton, our findings suggest that day-to-day fluctuations in air pollution increase the risk of ischemic stroke during the summer season, while medium term exposures are unrelated to stroke risk. The findings for medium term exposure should be interpreted cautiously due to limited individual-level risk factor data.
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Cites: J Epidemiol Community Health. 2002 Oct;56(10):773-912239204
OBJECTIVES: The objective of this article is to measure the contributions of age groups and causes of death to differences in mortality and life expectancy between residents of Inuit Nunangat and the rest of Canada. STUDY DESIGN: The geographic area of coverage includes communities within Inuit Nunangat, with the addition of Inuvik in the Northwest Territories. Deaths were compiled for 2 5-year periods, 1994 through 1998 and 1999 through 2003, with the mid-year centred on the 1996 and 2001 censuses. METHODS: Abridged life tables were constructed according to the revised Chiang method. Age decomposition of differences in life expectancy and cause-deleted life tables were calculated using a discrete approach. The age groups and causes contributing to differences in life expectancy between Inuit Nunangat and the rest of Canada were calculated. RESULTS: Specific age groups contribute more to the difference in life expectancy between Inuit Nunangat and the rest of Canada. For males, over 50% of the difference in life expectancy is due to excess mortality before 25 years of age, while for females nearly 65% is due to excess mortality after the age of 60. CONCLUSIONS: Cancer is a major contributor to the difference in life expectancy between residents of Inuit Nunangat and the rest of Canada; reduction in cancer rates would make the greatest contribution to gains in life expectancy. There are clear gender differences in life expectancy and mortality, with the total effect of mortality being greatest for males between 15 and 25 years of age and for females over the age of 60.
To describe community-driven alcohol policy for 78, primarily First Nations, Métis and Inuit, communities in Canada's three northern territories (Yukon, Northwest Territories and Nunavut) between 1970 and 2008. This is a first step to understanding the policy-oriented prevention system that has evolved in these areas over time.
Regulatory data were compiled from Part II of the Territorial Gazette Indices and the Revised Statutes and Regulations of each territory. Regulations were categorized as open, restricted, prohibited or other.
The number of communities with some form of regulation has increased steadily over time with half of the sample communities adopting some form of regulation between 1970 and 2008. The use of prohibition as a policy choice peaked in 1980 but has remained relatively steady since that time. There has been a steady increase in the adoption of other kinds of restrictions. Communities with regulations tend to have smaller and younger populations, a greater percentage of people with First Nations, Métis or Inuit origin and are more geographically isolated than those with no regulation.
This is the first time alcohol control policies have been compiled and described for the Canadian north. The dataset records the collective energies being put into community problem solving and provides a means to interpret the prevalence of health and social problems linked to alcohol use in these communities over time.
Administrative datasets often lack information about individual characteristics such as Aboriginal identity and income. However, these datasets frequently contain individual-level geographic information (such as postal codes). This paper explains the methodology for creating Geozones, which are area-based thresholds of population characteristics derived from census data, which can be used in the analysis of social or economic differences in health and health service utilization.
With aggregate 2006 Census information at the Dissemination Area level, population concentration and exposure for characteristics of interest are analysed using threshold tables and concentration curves. Examples are presented for the Aboriginal population and for income gradients.
The patterns of concentration of First Nations people, Métis, and Inuit differ from those of non-Aboriginal people and between urban and rural areas. The spatial patterns of concentration and exposure by income gradients also differ.
The Geozones method is a relatively easy way of identifying areas with lower and higher concentrations of subgroups. Because it is ecological-based, Geozones has the inherent strengths and weaknesses of this approach.
Living in a community with lower socioeconomic status is associated with higher mortality. However, few studies have examined associations between community socioeconomic characteristics and mortality among the First Nations population.
The 1991-to-2006 Census Mortality and Cancer Cohort follow-up, which tracked a 15% sample of Canadians aged 25 or older, included 57,300 respondents who self-identified as Registered First Nations people or Indian band members. The Community Well-Being Index (CWB), a measure of the social and economic well-being of communities, consists of income, education, labour force participation, and housing components. A dichotomous variable was used to indicate residence in a community with a CWB score above or below the average for First Nations communities. Age-standardized mortality rates (ASMRs) were calculated for First Nations cohort members in communities with CWB scores above and below the First Nations average. Cox proportional hazards models examined the impact of CWB when controlling for individual characteristics.
The ASMR for First Nations cohort members in communities with a below-average CWB was 1,057 per 100,000 person-years at risk, compared with 912 for those in communities with an above-average CWB score. For men, living in a community with below-average income and labour force participation CWB scores was associated with an increased hazard of death, even when individual socioeconomic characteristics were taken into account. Women in communities with below-average income scores had an increased hazard of death.
First Nations people in communities with below-average CWB scores tended to have higher mortality rates. For some components of the CWB, effects remained even when individual socioeconomic characteristics were taken into account.
Recent studies suggest that chronic exposure to air pollution can promote the development of diabetes. However, whether this relationship actually translates into an increased risk of mortality attributable to diabetes is uncertain.
We evaluated the association between long-term exposure to ambient fine particulate matter (PM2.5) and diabetes-related mortality in a prospective cohort analysis of 2.1 million adults from the 1991 Canadian census mortality follow-up study. Mortality information, including ~5,200 deaths coded as diabetes being the underlying cause, was ascertained by linkage to the Canadian Mortality Database from 1991 to 2001. Subject-level estimates of long-term exposure to PM2.5 were derived from satellite observations. The hazard ratios (HRs) for diabetes-related mortality were related to PM2.5 and adjusted for individual-level and contextual variables using Cox proportional hazards survival models.
Mean PM2.5 exposure levels for the entire population were low (8.7 µg/m3; SD, 3.9 µg/m3; interquartile range, 6.2 µg/m3). In fully adjusted models, a 10-µg/m3 elevation in PM2.5 exposure was associated with an increase in risk for diabetes-related mortality (HR, 1.49; 95% CI, 1.37-1.62). The monotonic change in risk to the population persisted to PM2.5 concentration
Many First Nations children live in communities that face diverse social and health challenges compared with their non-Aboriginal peers, including some of the most socio-economically challenging situations in Canada. These differences can be seen in broad indicators of the social determinants of health. Studies of mortality in Aboriginal populations across Canada are often restricted by the lack of Aboriginal identifiers on national death records. While some studies have utilised a record-linkage approach, this is often not possible for the entire country or for recent data. Some researchers have adopted a geographic approach and examined mortality and morbidity in areas that have a high percentage of Aboriginal identity residents, and have uniformly reported elevated rates of mortality and morbidity compared with other areas. The purpose of this article was to examine child and youth mortality (aged 1 to 19 years) in areas where a high percentage of the population identified as First Nations in comparison with areas where there is a low percentage of Aboriginal identity residents.
Using a geographic threshold table approach, areas with a high percentage of Aboriginal identity peoples were classified as either First Nations, Métis, or Inuit communities based on the predominant identity group. The upper one-third of the total Aboriginal population distribution was used as a cut-off for high percentage First Nations areas, where 97.7% of the population aged 1-19 were of First Nations identity in 2006 (N=140 779). Mortality rates were then calculated for high-percentage First Nations identity areas and compared with low-percentage Aboriginal identity areas, excluding high-percentage Métis or Inuit identity areas. Deaths were aggregated for the 3 years surrounding the 2001 and 2006 census periods, and a total of 473 deaths were recorded for 2000-2002 and 493 deaths for 2005-2007. Analysis was facilitated via the correspondence of six-digit residential postal codes on vital statistics records to census geographical areas using automated geo-coding software (Statistics Canada; PCCF+).
Age-standardized mortality rates for children and youth in high-percentage First Nations identity areas were significantly higher than in low-percentage Aboriginal identity areas. The rate ratio for all-cause mortality for boys was 3.2 (CI: 2.9-3.6) for 2005-2007 and 3.6 (CI: 3.2-4.2) for girls. Mortality rates for injuries had the largest difference, with rate ratios of 4.7 (CI: 4.0-5.5) and 5.3 (CI:4.5-6.3) for boys in 2000-2002 and 2005-2007 and 5.5 (CI: 4.4-6.8) and 8.3 (CI: 6.8-10.1) for girls in the same period.
A strength of this study is that it is the first to use national-level vital statistics registration data across two time periods to report mortality by cause for children and youth living in high-percentage First Nations areas. Vital events were geographically coded to high-percentage First Nations identity areas and compared with low-percentage Aboriginal identity areas at the Dissemination Areas level. This area-based methodology allows for mortality to be calculated for children and youth by sex and by detailed cause of death for multiple time periods. The results provide key evidence for the persistent differences in the causes of death for children and youth living in high-percentage First Nations identity areas.
